Liquid trap for refrigerating systems



June 10, 1930. A. c. SCHICKLER' LIQUID TRAP FOR REFRIGERATING SYSTEMS 7 Original Filed June 30. 1927 gmewfoz Patented June 10, 1930 PATENT OFFICE mnar c. or cmvmn,

OHIO, ASSIGNOB IO E. mm 0.!

cmvnmnn, OHIO LIQUID TRAP FOB BEFBIGEBATING SYSTEMS Original application filed June 30, 1927, Serial 110. 202,724. Divided and this application filed June 80,

- 1827. Serial No. 202,725.

This invention relates to liquid traps for refrigerating systems, such traps as are use for controlling the flow of the refrigerant, either liquid or gas or both, through the circulating or transmitting conduits. This application is a division of my application for refrigerating system filed of even date herewith, Ser. No. 202,724.

' Broadly speaking the invention provides an improved form of trap of the liquid seal type. constructed and arranged to permit practically unimpeded flow in one direction and to-prevent flow in the other direction by a resistance depending upon the proportions and arrangements of the liquid seal and the legs of sealing liquid produced therein'under va g conditions.

' The object of the present invention is to provide an improved trap of this kind which 20 reduces the tendency of the moving refrigerant to blow, swee or spray the sealing liquid bodily out of t e trap and thereby to displace it from its proper place in the system and interfere with proper action.

g5 A further object is to prov1 de a trap in which the ports, passages and chambers are so arranged asto limit the rate of flow of the refrigerant through the trap and therefore control its possible efl'ect upon the sealing, liquid, and particularly to control the 'flow by balancing the pressures of different portions of the sealing liquid in one leg, so that its escape from the apparatus is prevented.

Further objects of the invention are in part obvious and in part will appear more in detail hereinafter.

In the drawings, which represent one suitable embodiment of the invention, Fig. 1 is a plan view; Fig. 2 is a sectional elevation on the line 22, Fig. 1; and Fig. 3 is a similar view illustrating the effect on the sealing liq- The liquid trap shown for purposes of illustration in the drawings comprises an outer shell or casing 1 of cylindrical form in plan viewhaving a bottom 2 and a to 3. A11 inlet conducting pipe 4 is led into t e center of the to and extends to the bottom 2, which it may a ut for purposes of support, if necesforined by slotting or recessmg sary. provided with one or more lateral ports or openings 5 formed, for example, by cutting away opposite sides of the p1pe to provide the two openings shown. The outlet pipefi enters the 5'. 1e wall of the casing and extends radially into its chamber into close neigh-' borin relation with the pipe 4. The inner end 0 pipe 6 is closed by a cross wall 7 and it is provided in its side, near the pipe 4, with a lateral port 8, which lies 'ust above an inner dome 9 of inverted cup 5 ape similar to the shell 1 and concentric therewith. The upper wall of said dome is spaced slightly below the pipe 6 so as to shield or bafile access to the port 7 8 thereof. and the side wall of the dome is provided with a port 10, while its lower edge, where it meets the bottom 2 of the shell is provided with shallow openings or the edges o the dome wall.

The joints of the metal are sealed, such as by a welding or brazing operation, at the sev-' eral points marked a, so that the only access to and from the cavities and chambers within the trap is through the passages in the two conduits 4, 6. Conduit 4 is the one by which the refrigerant is conducted to the trap, while the pipe 6 is the outlet. These two pipes are of relatively small dimensions, say inside diameter, and are usually of like size. The ports or o enings 8 and 10 are also relatively small an arc of approximately the same diameter. In any event, port 10 is at least as large as the port 8.

Within the casing is placed a quantity (if recesses 11 Near its lower end said inlet pipe is trap at the time of its assembly in a refrigsuch as by introducing it the other of the conduits 4 introduced in a careending upon the e parts and the crating system, through one or or 6. This mercury is fully measured quantity de size and proportions of t 'mercury in the trap. The normal level of mercury, indicated at A, Fig. 2, is slightly above the upper edges of the ports or openings 5 in the pipe 4, so that said ports or openings, as well as the ports 11 in the dome 9, are normally completely submerged in the mercury, which finds the same level in the.

central passage in conduit 4, in the co-axial chamber 12, Within the dome 9 and in the annular chamber 13 in the outer shell outside of the dome.

This arrangement is essentially a U-tube with one column or leg of mercury in the pipe 4 surmounted by the pressure of the gas or liquid above it and another leg of mercury in the chambers 12, 13 surmounted by the pressure of the gas or liquid in said chambers and in the passage of the conduit 6. Upon any differential of pressure in either direc-' tion one mercury leg is depressed and the other rises. It will be obvious that if the pressure in pipe 4 becomes greater than the pressure in pipe 6 the mercury leg in pipe 4 is depressed until its upper surface is pushed down beneath the edges of the orifices 5, whereupon gas or liquid, as the case may be, flows from pipe 4 through the orifices 5 into the chamber 12. Such flow displaces a relatively small quantityof mercury, to wit, a

volume of mercury having the same cross sec-' tional area as the channel in pipe 4 and a height equal to the difference in level between the level A and the upper edges of the orifices 5. This small quantity of mercury when forced over into the chambers 12 and 13 does not materially raise the level of mercury therein, due to their large area. As a consequence-a very slight differential of pressure of the pipe 4 over the pipe 6 will permit flow in the direction stated and the trap can be adiusted to offer practically no resistance to flow in this direction. However. if the pres sure in, the pipe 6 rises above that in pipe 4, or if the pressure in pipe 4 falls, the leg of mercury in chambers 12 and 13 is depressed and the leg of mercury in the pipe 4 rises. In this case, however, the cross sectional areas of the.

two legs of mercury are so widely different that the same very small depression of the mercury in chambers 12, 13 produces a very material rise of mercury in pipe 4, even to a height of four to eight feet if desired, and the quantity of mercury initially installed in the trap may be so chosen as to produce a sufliciently high leg in pipe 4 to ractically absolutely prevent any flow ackwardly from pipe 6 to pipe 4 at the differentials of pressure that are encountered in normal or even abnormal operation of the system in which the trap is installed.

One important feature of the present invention is the arrangement to prevent any rush of gas or liquid through the trap to pipe 6 from sweeping or blowing or spraying the mercury out of the trap. The arrangement of the parts is such that if the trap is physically turned upside down the mercury, seek ing its level at all times, follows the walls of the chambers and finds no escape to either of the pipes 4 or 6, according to the principles of my prior applications referred to. Even when the tra 1s completely inverted the mercury level will not reach the port 8 and cannot flow into the pipe'6. Moreover, as the gas or liquid flows from pipe 4 through the ports 5, it enters chamber 12, from which it issues into chamber 13 through the small port 10.

This arrangement limits the rate of exit fromv chamber 13 to the rate of entrance thereto. Therefore, no violent effect is produced, such as would be possible if the mercury could sweep into a single chamber and thence blow freely out through an exit to the pipe 6. With this latter arrangement the violence of the passage of the gas sometimes seems to vaporize or so finely divide the mercury as to spray it bodily out through the pipe 6, but the equalization of pressures in chambers 12 and 13 during passage of gas through the trap avoids disturbance of the mercury and insures its retention in its proper operating po- 1 sition.

Moreover, it is apparent that when the pressure in pipe 4 preponderates over that in pipe 6 the first bubble of gas enters chamber 12 by bubbling up through the mercury. The first effect of this entering gas is to very slightly increase the pressure in chamber 12 over that in chamber 13, which has a tendency to depress the mercury in chamber 12 and elevate it in chamber 13. While, of course, we are dealing with very small dimensions, which are exaggerated in Fig. 3 for simplicity of illustration, the net efiect seems to be to depress the surface of the liquid in chamber 12 into somewhat saucer shape,

completely exposing the openings 5 and permitting the gas to flow into chamber 12 in a steady stream instead of as a succession of bubbles. The operation is therefore more quiet and the mercury is left more or less quiescent, merely shifting the level of differ ent portions of its upper surface with variations in pressure conditions.

- In my co-pending application of which this is a division, the invention has been described as used in an absorption type refrigerating apparatus. However, it is obvious that it is useful in refrigerating systems of-other typesand in fact in any place where it is desired to limit or control the passage-of gas or liquid so that its flow in one direct on 1s either resisted to a greater extent than in the other direction or in fact may be practically stopped. 7

What I claim is: 1. A liquid trap of the kind described, comprising a hollow shell provided with an entrance pipe opening into its lower portion, a hollow dome dividing the cavity in said shell into two chambers communicating at a-low level, said dome being provided with a vent,

10 and an exit pipe communicating with the outer chamber. 2. A liquid trap of the kind described, comprising a hollow shell provided with two chambers communicating near their bottoms,-

I an entrance pipe communicating with one chamber, an exit pipe communicating with the other chamber, and means for equalizing the pressures in said two chambers. I

3. A device for controlling the flow of refrigerant in refrigerating systems, comprising two chambers containlng a sealing liquid and communicating with each other .both above and below the normal. level of the surface of said liquid an entrance conduit communicating with one chamber below said level, and an exit conduit communicating with the other chamber.

4. A device for controlling the flow of refrigerant in refrigerating systems, comprisingtwo chambers containing a sealing liquid and communicating with each other below the normal level of the surface of said liquid and provided with a communicating port between them above said level, an entrance conduit communicating with one chamber below said level, and an exit conduit havinga supply port no larger than said first named art and communicating with the other cham r. In testimony whereof I hereby aflix my 40 signature. Q

ALBERT C. SOHIGKLER. 

